1. Field of the Invention
The present invention relates to an antenna frame, an integrated circuit (IC) card and a manufacturing method thereof. The antenna frame is used for IC cards or IC tags which are generally called xe2x80x9cIC cardsxe2x80x9d in this specification hereinafter and send and receive signals using a non-contact system. More particularly, the present invention relates to an IC card and manufacturing method thereof, the characteristic feature of which is the method of holding an antenna of the IC card.
2. Description of the Related Art
The IC card is composed as follows. A semiconductor element is electrically connected with and mounted on an antenna which is formed into a flat coil-shape, for sending and receiving signals, and a film which forms the outside of the IC card is laminated on both sides of the antenna and semiconductor element. In this connection, there is provided a tag product which is used for the discrimination of baggage, and this tag product is similar to the IC card. In the same manner as that of the IC card, this tag product is composed in such a manner that a semiconductor element is mounted on an antenna and a film is laminated on both sides of the antenna and semiconductor element. In the same manner as that of the IC card, the tag product is advantageous in that information can be sent and received in a non-contact system so that baggage can be effectively discriminated. In this connection, in this specification, the IC card includes a product such a tag product which is provided with an antenna and semiconductor element and is capable of sending and receiving a signal using a non-contact system.
When the IC card is manufactured, a metal sheet is subjected to punching or etching so that the metal sheet can be formed into a predetermined coil-shape antenna, and a semiconductor element is electrically connected with and mounted on the antenna, and then a film is laminated on both sides of the antenna and semiconductor element. FIG. 16 is a view showing a state in which a metal sheet is subjected to punching and formed into an antenna 10, and a semiconductor element 12 is mounted on the antenna 10. In this case, the tape 14 is made to adhere to the antenna 10 as a support member so that the coil-shaped antenna 10 cannot be deformed in the case of conveying the antenna or laminating the film on both sides of the antenna and semiconductor element. The periphery of the antenna 10 is supported by the frame 16.
FIG. 17 is a view showing an example in which the antenna 10 and the semiconductor element 12 are interposed between the protective films 18 on both sides. The protective films 18 may be previously removed before the outside film for the IC card is laminated. Alternatively, the protective films 18 may be left being interposed between the outside film and the antenna 10 and semiconductor element 12.
In this connection, it can be considered that a very large number of IC cards are used and discarded after they have been used. Due to the foregoing, as the number of the used IC cards has increased, disposal of the IC cards becomes a big problem. As described before, according to the conventional method of manufacturing the IC card, the tape 14 and the protective film 18 are used to prevent the antenna from being moved, and further the film is laminated outside the antenna 10. The tape 14, protective film 18 and film, which covers the outside of the IC card, are made of synthetic resin such as polyvinyl chloride (PVC) or polyethylene terephthalate (PET). These synthetic resins used for the conventional IC card cannot be easily degraded in the nature. Even when these synthetic resins are incinerated, various environmental problems may be caused.
The present invention has been accomplished by considering a IC card which will be consumed in large quantities. It is an object of the present invention to provide an antenna frame used for the IC card, IC card and preferable manufacturing method thereof, characterized in that: the IC card can be easily discarded at low cost without affecting the natural environment; the IC card can be mass-produced because the manufacturing cost is low; and the IC card can be effectively used for many purposes.
According to the present invention there is provided an IC card comprising: a semiconductor element; an antenna electrically connected to said semiconductor element; and a supporting material for supporting said semiconductor element and said antenna, said supporting material being made of biodegradable resin.
The antenna is made of a material which can be easily oxidized and eroded. Particularly, the antenna is made of iron.
The antenna is a flat coil wound several times having an inner vacant area. A whole surface of said flat coil including said inner vacant area is entirely supported by said supporting material. Otherwise, the whole surface of said flat coil except for said inner vacant area is entirely supported by said supporting material.
An IC card further comprises a pair of films laminated to respective surfaces of said flat coil and said semiconductor element to form outer surfaces of said IC card and said pair of films are made of biodegradable resin or paper.
According to another aspect of the present invention, there is provided a method for manufacturing an IC card comprising the following steps of: mounting a semiconductor element on an antenna and electrically connecting said semiconductor element to said antenna; and supporting said semiconductor element and said antenna by means of supporting material made of biodegradable resin.
The supporting material is made of liquid-like or paste-like biodegradable resin and said method further comprises: coating said antenna with said supporting material.
The supporting material is made of granular biodegradable resin and said method further comprises: melting said supporting material to support said antenna.
The antenna is a flat coil wound several times having an inner vacant area. In this case, the method comprises the following steps of: mounting a semiconductor element on said flat coil and electrically connecting said semiconductor element to said flat coil; arranging a pair of supporting sheets made of biodegradable resin over respective sides of said flat coil and said semiconductor element; and pressing said pair of supporting sheets toward said flat coil and said semiconductor element.
The method further comprises a step of: laminating a pair of films, made of biodegradable resin or paper, to respective surfaces of said flat coil and said semiconductor element to form external surfaces of said IC card.
According to a still another aspect of the present invention, there is provided an antenna frame used for an IC card comprising: an antenna formed as a flat coil wound several times having an inner vacant area, said antenna being made by punching or etching a thin metal strip and having an outermost loop partially connected to and supported by an outer frame of said thin metal strip, and said antenna having respective innermost and outermost terminals; one of said innermost and outermost terminals having an accommodation hole in which a semiconductor element is to be accommodated; and supporting material for supporting said antenna to maintain its shape, said supporting material being made of biodegradable resin.
In accordance with a further aspect of the present invention, there is provided an IC card comprising: an antenna formed as a flat coil wound several times having an inner vacant area, said antenna being made by punching or etching a thin metal strip and having an outermost loop partially connected to and supported by an outer frame of said thin metal strip, and said antenna having respective innermost and outermost terminals; a semiconductor element electrically connected to said innermost and outermost terminals, respectively; one of said innermost and outermost terminals having an accommodation hole in which said semiconductor element is accommodated; and supporting material for supporting said semiconductor element and said antenna to maintain their form, said supporting material being made of biodegradable resin.
The IC card further comprises a wiring pattern film for electrically connecting terminals of said semiconductor element to said innermost and outermost terminals of the antenna, respectively.
The IC card further comprises a pair of films laminated to respective surfaces of said flat coil and said semiconductor element to form external surfaces of said IC card and said pair of films are made of biodegradable resin or paper.